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|
.file "asin.s"
// Copyright (c) 2000 - 2003 Intel Corporation
// All rights reserved.
//
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// * The name of Intel Corporation may not be used to endorse or promote
// products derived from this software without specific prior written
// permission.
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Intel Corporation is the author of this code, and requests that all
// problem reports or change requests be submitted to it directly at
// http://www.intel.com/software/products/opensource/libraries/num.htm.
// History
//==============================================================
// 02/02/00 Initial version
// 08/17/00 New and much faster algorithm.
// 08/31/00 Avoided bank conflicts on loads, shortened |x|=1 path,
// fixed mfb split issue stalls.
// 12/19/00 Fixed small arg cases to force inexact, or inexact and underflow.
// 08/02/02 New and much faster algorithm II
// 02/06/03 Reordered header: .section, .global, .proc, .align
// Description
//=========================================
// The asin function computes the principal value of the arc sine of x.
// asin(0) returns 0, asin(1) returns pi/2, asin(-1) returns -pi/2.
// A domain error occurs for arguments not in the range [-1,+1].
//
// The asin function returns the arc sine in the range [-pi/2, +pi/2] radians.
//
// There are 8 paths:
// 1. x = +/-0.0
// Return asin(x) = +/-0.0
//
// 2. 0.0 < |x| < 0.625
// Return asin(x) = x + x^3 *PolA(x^2)
// where PolA(x^2) = A3 + A5*x^2 + A7*x^4 +...+ A35*x^32
//
// 3. 0.625 <=|x| < 1.0
// Return asin(x) = sign(x) * ( Pi/2 - sqrt(R) * PolB(R))
// Where R = 1 - |x|,
// PolB(R) = B0 + B1*R + B2*R^2 +...+B12*R^12
//
// sqrt(R) is approximated using the following sequence:
// y0 = (1 + eps)/sqrt(R) - initial approximation by frsqrta,
// |eps| < 2^(-8)
// Then 3 iterations are used to refine the result:
// H0 = 0.5*y0
// S0 = R*y0
//
// d0 = 0.5 - H0*S0
// H1 = H0 + d0*H0
// S1 = S0 + d0*S0
//
// d1 = 0.5 - H1*S1
// H2 = H1 + d0*H1
// S2 = S1 + d0*S1
//
// d2 = 0.5 - H2*S2
// S3 = S3 + d2*S3
//
// S3 approximates sqrt(R) with enough accuracy for this algorithm
//
// So, the result should be reconstracted as follows:
// asin(x) = sign(x) * (Pi/2 - S3*PolB(R))
//
// But for optimization perposes the reconstruction step is slightly
// changed:
// asin(x) = sign(x)*(Pi/2 - PolB(R)*S2) + sign(x)*d2*S2*PolB(R)
//
// 4. |x| = 1.0
// Return asin(x) = sign(x)*Pi/2
//
// 5. 1.0 < |x| <= +INF
// A domain error occurs for arguments not in the range [-1,+1]
//
// 6. x = [S,Q]NaN
// Return asin(x) = QNaN
//
// 7. x is denormal
// Return asin(x) = x + x^3,
//
// 8. x is unnormal
// Normalize input in f8 and return to the very beginning of the function
//
// Registers used
//==============================================================
// Floating Point registers used:
// f8, input, output
// f6, f7, f9 -> f15, f32 -> f63
// General registers used:
// r3, r21 -> r31, r32 -> r38
// Predicate registers used:
// p0, p6 -> p14
//
// Assembly macros
//=========================================
// integer registers used
// scratch
rTblAddr = r3
rPiBy2Ptr = r21
rTmpPtr3 = r22
rDenoBound = r23
rOne = r24
rAbsXBits = r25
rHalf = r26
r0625 = r27
rSign = r28
rXBits = r29
rTmpPtr2 = r30
rTmpPtr1 = r31
// stacked
GR_SAVE_PFS = r32
GR_SAVE_B0 = r33
GR_SAVE_GP = r34
GR_Parameter_X = r35
GR_Parameter_Y = r36
GR_Parameter_RESULT = r37
GR_Parameter_TAG = r38
// floating point registers used
FR_X = f10
FR_Y = f1
FR_RESULT = f8
// scratch
fXSqr = f6
fXCube = f7
fXQuadr = f9
f1pX = f10
f1mX = f11
f1pXRcp = f12
f1mXRcp = f13
fH = f14
fS = f15
// stacked
fA3 = f32
fB1 = f32
fA5 = f33
fB2 = f33
fA7 = f34
fPiBy2 = f34
fA9 = f35
fA11 = f36
fB10 = f35
fB11 = f36
fA13 = f37
fA15 = f38
fB4 = f37
fB5 = f38
fA17 = f39
fA19 = f40
fB6 = f39
fB7 = f40
fA21 = f41
fA23 = f42
fB3 = f41
fB8 = f42
fA25 = f43
fA27 = f44
fB9 = f43
fB12 = f44
fA29 = f45
fA31 = f46
fA33 = f47
fA35 = f48
fBaseP = f49
fB0 = f50
fSignedS = f51
fD = f52
fHalf = f53
fR = f54
fCloseTo1Pol = f55
fSignX = f56
fDenoBound = f57
fNormX = f58
fX8 = f59
fRSqr = f60
fRQuadr = f61
fR8 = f62
fX16 = f63
// Data tables
//==============================================================
RODATA
.align 16
LOCAL_OBJECT_START(asin_base_range_table)
// Ai: Polynomial coefficients for the asin(x), |x| < .625000
// Bi: Polynomial coefficients for the asin(x), |x| > .625000
data8 0xBFDAAB56C01AE468 //A29
data8 0x3FE1C470B76A5B2B //A31
data8 0xBFDC5FF82A0C4205 //A33
data8 0x3FC71FD88BFE93F0 //A35
data8 0xB504F333F9DE6487, 0x00003FFF //B0
data8 0xAAAAAAAAAAAAFC18, 0x00003FFC //A3
data8 0x3F9F1C71BC4A7823 //A9
data8 0x3F96E8BBAAB216B2 //A11
data8 0x3F91C4CA1F9F8A98 //A13
data8 0x3F8C9DDCEDEBE7A6 //A15
data8 0x3F877784442B1516 //A17
data8 0x3F859C0491802BA2 //A19
data8 0x9999999998C88B8F, 0x00003FFB //A5
data8 0x3F6BD7A9A660BF5E //A21
data8 0x3F9FC1659340419D //A23
data8 0xB6DB6DB798149BDF, 0x00003FFA //A7
data8 0xBFB3EF18964D3ED3 //A25
data8 0x3FCD285315542CF2 //A27
data8 0xF15BEEEFF7D2966A, 0x00003FFB //B1
data8 0x3EF0DDA376D10FB3 //B10
data8 0xBEB83CAFE05EBAC9 //B11
data8 0x3F65FFB67B513644 //B4
data8 0x3F5032FBB86A4501 //B5
data8 0x3F392162276C7CBA //B6
data8 0x3F2435949FD98BDF //B7
data8 0xD93923D7FA08341C, 0x00003FF9 //B2
data8 0x3F802995B6D90BDB //B3
data8 0x3F10DF86B341A63F //B8
data8 0xC90FDAA22168C235, 0x00003FFF // Pi/2
data8 0x3EFA3EBD6B0ECB9D //B9
data8 0x3EDE18BA080E9098 //B12
LOCAL_OBJECT_END(asin_base_range_table)
.section .text
GLOBAL_LIBM_ENTRY(asin)
asin_unnormal_back:
{ .mfi
getf.d rXBits = f8 // grab bits of input value
// set p12 = 1 if x is a NaN, denormal, or zero
fclass.m p12, p0 = f8, 0xcf
adds rSign = 1, r0
}
{ .mfi
addl rTblAddr = @ltoff(asin_base_range_table),gp
// 1 - x = 1 - |x| for positive x
fms.s1 f1mX = f1, f1, f8
addl rHalf = 0xFFFE, r0 // exponent of 1/2
}
;;
{ .mfi
addl r0625 = 0x3FE4, r0 // high 16 bits of 0.625
// set p8 = 1 if x < 0
fcmp.lt.s1 p8, p9 = f8, f0
shl rSign = rSign, 63 // sign bit
}
{ .mfi
// point to the beginning of the table
ld8 rTblAddr = [rTblAddr]
// 1 + x = 1 - |x| for negative x
fma.s1 f1pX = f1, f1, f8
adds rOne = 0x3FF, r0
}
;;
{ .mfi
andcm rAbsXBits = rXBits, rSign // bits of |x|
fmerge.s fSignX = f8, f1 // signum(x)
shl r0625 = r0625, 48 // bits of DP representation of 0.625
}
{ .mfb
setf.exp fHalf = rHalf // load A2 to FP reg
fma.s1 fXSqr = f8, f8, f0 // x^2
// branch on special path if x is a NaN, denormal, or zero
(p12) br.cond.spnt asin_special
}
;;
{ .mfi
adds rPiBy2Ptr = 272, rTblAddr
nop.f 0
shl rOne = rOne, 52 // bits of 1.0
}
{ .mfi
adds rTmpPtr1 = 16, rTblAddr
nop.f 0
// set p6 = 1 if |x| < 0.625
cmp.lt p6, p7 = rAbsXBits, r0625
}
;;
{ .mfi
ldfpd fA29, fA31 = [rTblAddr] // A29, fA31
// 1 - x = 1 - |x| for positive x
(p9) fms.s1 fR = f1, f1, f8
// point to coefficient of "near 1" polynomial
(p7) adds rTmpPtr2 = 176, rTblAddr
}
{ .mfi
ldfpd fA33, fA35 = [rTmpPtr1], 16 // A33, fA35
// 1 + x = 1 - |x| for negative x
(p8) fma.s1 fR = f1, f1, f8
(p6) adds rTmpPtr2 = 48, rTblAddr
}
;;
{ .mfi
ldfe fB0 = [rTmpPtr1], 16 // B0
nop.f 0
nop.i 0
}
{ .mib
adds rTmpPtr3 = 16, rTmpPtr2
// set p10 = 1 if |x| = 1.0
cmp.eq p10, p0 = rAbsXBits, rOne
// branch on special path for |x| = 1.0
(p10) br.cond.spnt asin_abs_1
}
;;
{ .mfi
ldfe fA3 = [rTmpPtr2], 48 // A3 or B1
nop.f 0
adds rTmpPtr1 = 64, rTmpPtr3
}
{ .mib
ldfpd fA9, fA11 = [rTmpPtr3], 16 // A9, A11 or B10, B11
// set p11 = 1 if |x| > 1.0
cmp.gt p11, p0 = rAbsXBits, rOne
// branch on special path for |x| > 1.0
(p11) br.cond.spnt asin_abs_gt_1
}
;;
{ .mfi
ldfpd fA17, fA19 = [rTmpPtr2], 16 // A17, A19 or B6, B7
// initial approximation of 1 / sqrt(1 - x)
frsqrta.s1 f1mXRcp, p0 = f1mX
nop.i 0
}
{ .mfi
ldfpd fA13, fA15 = [rTmpPtr3] // A13, A15 or B4, B5
fma.s1 fXCube = fXSqr, f8, f0 // x^3
nop.i 0
}
;;
{ .mfi
ldfe fA5 = [rTmpPtr2], 48 // A5 or B2
// initial approximation of 1 / sqrt(1 + x)
frsqrta.s1 f1pXRcp, p0 = f1pX
nop.i 0
}
{ .mfi
ldfpd fA21, fA23 = [rTmpPtr1], 16 // A21, A23 or B3, B8
fma.s1 fXQuadr = fXSqr, fXSqr, f0 // x^4
nop.i 0
}
;;
{ .mfi
ldfe fA7 = [rTmpPtr1] // A7 or Pi/2
fma.s1 fRSqr = fR, fR, f0 // R^2
nop.i 0
}
{ .mfb
ldfpd fA25, fA27 = [rTmpPtr2] // A25, A27 or B9, B12
nop.f 0
(p6) br.cond.spnt asin_base_range;
}
;;
{ .mfi
nop.m 0
(p9) fma.s1 fH = fHalf, f1mXRcp, f0 // H0 for x > 0
nop.i 0
}
{ .mfi
nop.m 0
(p9) fma.s1 fS = f1mX, f1mXRcp, f0 // S0 for x > 0
nop.i 0
}
;;
{ .mfi
nop.m 0
(p8) fma.s1 fH = fHalf, f1pXRcp, f0 // H0 for x < 0
nop.i 0
}
{ .mfi
nop.m 0
(p8) fma.s1 fS = f1pX, f1pXRcp, f0 // S0 for x > 0
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fRQuadr = fRSqr, fRSqr, f0 // R^4
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fB11 = fB11, fR, fB10
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fB1 = fB1, fR, fB0
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fB5 = fB5, fR, fB4
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fB7 = fB7, fR, fB6
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fB3 = fB3, fR, fB2
nop.i 0
}
;;
{ .mfi
nop.m 0
fnma.s1 fD = fH, fS, fHalf // d0 = 1/2 - H0*S0
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fR8 = fRQuadr, fRQuadr, f0 // R^4
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fB9 = fB9, fR, fB8
nop.i 0
}
;;
{.mfi
nop.m 0
fma.s1 fB12 = fB12, fRSqr, fB11
nop.i 0
}
{.mfi
nop.m 0
fma.s1 fB7 = fB7, fRSqr, fB5
nop.i 0
}
;;
{.mfi
nop.m 0
fma.s1 fB3 = fB3, fRSqr, fB1
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fH = fH, fD, fH // H1 = H0 + H0*d0
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fS = fS, fD, fS // S1 = S0 + S0*d0
nop.i 0
}
;;
{.mfi
nop.m 0
fma.s1 fPiBy2 = fPiBy2, fSignX, f0 // signum(x)*Pi/2
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fB12 = fB12, fRSqr, fB9
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fB7 = fB7, fRQuadr, fB3
nop.i 0
}
;;
{.mfi
nop.m 0
fnma.s1 fD = fH, fS, fHalf // d1 = 1/2 - H1*S1
nop.i 0
}
{ .mfi
nop.m 0
fnma.s1 fSignedS = fSignX, fS, f0 // -signum(x)*S1
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fCloseTo1Pol = fB12, fR8, fB7
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fH = fH, fD, fH // H2 = H1 + H1*d1
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fS = fS, fD, fS // S2 = S1 + S1*d1
nop.i 0
}
;;
{ .mfi
nop.m 0
// -signum(x)* S2 = -signum(x)*(S1 + S1*d1)
fma.s1 fSignedS = fSignedS, fD, fSignedS
nop.i 0
}
;;
{.mfi
nop.m 0
fnma.s1 fD = fH, fS, fHalf // d2 = 1/2 - H2*S2
nop.i 0
}
;;
{ .mfi
nop.m 0
// signum(x)*(Pi/2 - PolB*S2)
fma.s1 fPiBy2 = fSignedS, fCloseTo1Pol, fPiBy2
nop.i 0
}
{ .mfi
nop.m 0
// -signum(x)*PolB * S2
fma.s1 fCloseTo1Pol = fSignedS, fCloseTo1Pol, f0
nop.i 0
}
;;
{ .mfb
nop.m 0
// final result for 0.625 <= |x| < 1
fma.d.s0 f8 = fCloseTo1Pol, fD, fPiBy2
// exit here for 0.625 <= |x| < 1
br.ret.sptk b0
}
;;
// here if |x| < 0.625
.align 32
asin_base_range:
{ .mfi
nop.m 0
fma.s1 fA33 = fA33, fXSqr, fA31
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fA15 = fA15, fXSqr, fA13
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fA29 = fA29, fXSqr, fA27
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fA25 = fA25, fXSqr, fA23
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fA21 = fA21, fXSqr, fA19
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fA9 = fA9, fXSqr, fA7
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fA5 = fA5, fXSqr, fA3
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fA35 = fA35, fXQuadr, fA33
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fA17 = fA17, fXQuadr, fA15
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fX8 = fXQuadr, fXQuadr, f0 // x^8
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fA25 = fA25, fXQuadr, fA21
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fA9 = fA9, fXQuadr, fA5
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fA35 = fA35, fXQuadr, fA29
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fA17 = fA17, fXSqr, fA11
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fX16 = fX8, fX8, f0 // x^16
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fA35 = fA35, fX8, fA25
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fA17 = fA17, fX8, fA9
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fBaseP = fA35, fX16, fA17
nop.i 0
}
;;
{ .mfb
nop.m 0
// final result for |x| < 0.625
fma.d.s0 f8 = fBaseP, fXCube, f8
// exit here for |x| < 0.625 path
br.ret.sptk b0
}
;;
// here if |x| = 1
// asin(x) = sign(x) * Pi/2
.align 32
asin_abs_1:
{ .mfi
ldfe fPiBy2 = [rPiBy2Ptr] // Pi/2
nop.f 0
nop.i 0
}
;;
{.mfb
nop.m 0
// result for |x| = 1.0
fma.d.s0 f8 = fPiBy2, fSignX, f0
// exit here for |x| = 1.0
br.ret.sptk b0
}
;;
// here if x is a NaN, denormal, or zero
.align 32
asin_special:
{ .mfi
nop.m 0
// set p12 = 1 if x is a NaN
fclass.m p12, p0 = f8, 0xc3
nop.i 0
}
{ .mlx
nop.m 0
// smallest positive DP normalized number
movl rDenoBound = 0x0010000000000000
}
;;
{ .mfi
nop.m 0
// set p13 = 1 if x = 0.0
fclass.m p13, p0 = f8, 0x07
nop.i 0
}
{ .mfi
nop.m 0
fnorm.s1 fNormX = f8
nop.i 0
}
;;
{ .mfb
// load smallest normal to FP reg
setf.d fDenoBound = rDenoBound
// answer if x is a NaN
(p12) fma.d.s0 f8 = f8,f1,f0
// exit here if x is a NaN
(p12) br.ret.spnt b0
}
;;
{ .mfb
nop.m 0
nop.f 0
// exit here if x = 0.0
(p13) br.ret.spnt b0
}
;;
// if we still here then x is denormal or unnormal
{ .mfi
nop.m 0
// absolute value of normalized x
fmerge.s fNormX = f1, fNormX
nop.i 0
}
;;
{ .mfi
nop.m 0
// set p14 = 1 if normalized x is greater than or
// equal to the smallest denormalized value
// So, if p14 is set to 1 it means that we deal with
// unnormal rather than with "true" denormal
fcmp.ge.s1 p14, p0 = fNormX, fDenoBound
nop.i 0
}
;;
{ .mfi
nop.m 0
(p14) fcmp.eq.s0 p6, p0 = f8, f0 // Set D flag if x unnormal
nop.i 0
}
{ .mfb
nop.m 0
// normalize unnormal input
(p14) fnorm.s1 f8 = f8
// return to the main path
(p14) br.cond.sptk asin_unnormal_back
}
;;
// if we still here it means that input is "true" denormal
{ .mfb
nop.m 0
// final result if x is denormal
fma.d.s0 f8 = f8, fXSqr, f8
// exit here if x is denormal
br.ret.sptk b0
}
;;
// here if |x| > 1.0
// error handler should be called
.align 32
asin_abs_gt_1:
{ .mfi
alloc r32 = ar.pfs, 0, 3, 4, 0 // get some registers
fmerge.s FR_X = f8,f8
nop.i 0
}
{ .mfb
mov GR_Parameter_TAG = 61 // error code
frcpa.s0 FR_RESULT, p0 = f0,f0
// call error handler routine
br.cond.sptk __libm_error_region
}
;;
GLOBAL_LIBM_END(asin)
libm_alias_double_other (asin, asin)
LOCAL_LIBM_ENTRY(__libm_error_region)
.prologue
{ .mfi
add GR_Parameter_Y=-32,sp // Parameter 2 value
nop.f 0
.save ar.pfs,GR_SAVE_PFS
mov GR_SAVE_PFS=ar.pfs // Save ar.pfs
}
{ .mfi
.fframe 64
add sp=-64,sp // Create new stack
nop.f 0
mov GR_SAVE_GP=gp // Save gp
};;
{ .mmi
stfd [GR_Parameter_Y] = FR_Y,16 // STORE Parameter 2 on stack
add GR_Parameter_X = 16,sp // Parameter 1 address
.save b0, GR_SAVE_B0
mov GR_SAVE_B0=b0 // Save b0
};;
.body
{ .mib
stfd [GR_Parameter_X] = FR_X // STORE Parameter 1 on stack
add GR_Parameter_RESULT = 0,GR_Parameter_Y // Parameter 3 address
nop.b 0
}
{ .mib
stfd [GR_Parameter_Y] = FR_RESULT // STORE Parameter 3 on stack
add GR_Parameter_Y = -16,GR_Parameter_Y
br.call.sptk b0=__libm_error_support# // Call error handling function
};;
{ .mmi
add GR_Parameter_RESULT = 48,sp
nop.m 0
nop.i 0
};;
{ .mmi
ldfd f8 = [GR_Parameter_RESULT] // Get return result off stack
.restore sp
add sp = 64,sp // Restore stack pointer
mov b0 = GR_SAVE_B0 // Restore return address
};;
{ .mib
mov gp = GR_SAVE_GP // Restore gp
mov ar.pfs = GR_SAVE_PFS // Restore ar.pfs
br.ret.sptk b0 // Return
};;
LOCAL_LIBM_END(__libm_error_region)
.type __libm_error_support#,@function
.global __libm_error_support#
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